A lack of good grounding is undesirable and increases the risk of equipment failure. The absence of an effective grounding system can lead to various problems, such as instrumentation errors, harmonic distortion issues, power factor problems and a host of possible intermittent dilemmas. If fault currents have no path to the ground through a properly designed and maintained grounding system, they will find unintended paths. Furthermore, a good grounding system is also used to prevent damage to industrial plants and equipment and is therefore necessary in order to improve the reliability of equipment and reduce the likelihood of damage due to lightning or fault currents.
Over time, corrosive soils with high moisture content, high salt content, and high temperatures can degrade ground rods and their connections. So although the grounding system may have had low earth ground resistance values when initially installed, the resistance of the grounding system can increase if the ground rods, or other elements of a grounding system, corrode over time. Grounding testers are useful troubleshooting tools in dealing with such issues as intermittent electrical problems, which could be related to poor grounding or poor power quality. It is therefore desirable that all grounds and ground connections are checked on a regular basis.
During these periodic checks, if an increase in resistance of more than 20% is measured, investigation of the source of the problem is undertaken so that corrections may be made to lower the resistance (e.g., by replacing or adding ground rods to the ground system). Such periodic checks may involve conducting established techniques such as fall-of-potential tests, selective measurements, soil resistivity tests which may also form part of a geological survey, two-pole measurements and stakeless measurements. With present grounding test systems, in order to achieve accurate results, such tests tend to be extremely time consuming and labor intensive. In particular when dealing with measurements involving high voltage applications such as electricity pylons, the tests need to be conducted with caution.
According to the prior art, all the aforementioned grounding test procedures require a considerable amount of effort walking back and forth several times between the various electrodes connected to a testing device to ensure accuracy and/or perform multiple measurements. Specifically, once a testing device has been set up for implementing the aforementioned techniques according to the prior art, incorrect or anomalous results can occur due to inadequate contact between the electrodes and test device due to loose clips, insufficient conduction or unsuitable placement of the electrodes. Hence, it is generally necessary to adjust the set-up and repeat measurements in order to correct such results. For example, an operator may check all connections at the various electrodes, which are often placed at large distances from one another.
Performing this repeat measurement/correction procedure with a single operator tends to be extremely time-consuming and labor-intensive. In order to reduce the wasted time and effort associated with this procedure, a common solution to this problem is to provide more than one operator to conduct a single test procedure; however this is often not realistic or possible due to the availability of such further personnel. Furthermore, this solution is neither efficient nor convenient and incurs considerable extra costs.